<?php
/**
 * ==示例==
 * $smtp = new smtp($smtpserver, $smtpserverport, true, $smtpuser, $smtppass); //这里面的一个true是表示使用身份验证,否则不使用身份验证. 
 * $smtp->debug = true; //是否显示发送的调试信息 
 * $emailtype ＝ "HTML"; //信件类型，文本:text；网页：HTML 
 * $smtp->sendmail($smtpemailto, $smtpemailfrom, $emailsubject, $emailbody, $emailtype);
 */

class smtp {
     /* Public Variables */
     var $smtp_port;
     var $time_out;
     var $host_name;
     var $log_file;
     var $relay_host;
     var $debug;
     var $auth;
     var $user;
     var $pass;
     /* Private Variables */
     var $sock;
     /* Constractor */
     function smtp($relay_host = "", $smtp_port = 25, $auth = false, $user, $pass)
     {
             $this->debug = false;
             $this->smtp_port = $smtp_port;
             $this->relay_host = $relay_host;
             $this->time_out = 30; //is used in fsockopen()
             $this->auth = $auth; //auth
             $this->user = $user;
             $this->pass = $pass;
             $this->host_name = "localhost"; //is used in HELO command
             $this->log_file = "";
             $this->sock = false;
     }


     /* Main Function */
     function sendmail($to, $from, $subject = "", $body = "", $mailtype, $cc = "", $bcc = "", $additional_headers = "")
     {
             $mail_from = $this->get_address($this->strip_comment($from));
             $body = ereg_replace("(^|(\r\n))(\.)", "\1.\3", $body);
             $header .= "MIME-Version:1.0\r\n";
             if ($mailtype == "HTML") {
                 $header .= "Content-Type:text/html;charset=utf-8\r\n";
             }
             $header .= "To: " . $to . "\r\n";


             if ($cc != "") {
                 $header .= "Cc: " . $cc . "\r\n";
             }


             $header .= "From: $from<" . $from . ">\r\n";


             $header .= "Subject: " . $subject . "\r\n";


             $header .= $additional_headers;


             $header .= "Date: " . date("r") . "\r\n";


             $header .= "X-Mailer:By Redhat (PHP/" . phpversion() . ")\r\n";


             list($msec, $sec) = explode(" ", microtime());


             $header .= "Message-ID: <" . date("YmdHis", $sec) . "." . ($msec * 1000000) . "." . $mail_from . ">\r\n";


             $TO = explode(",", $this->strip_comment($to));


             if ($cc != "") {
                 $TO = array_merge($TO, explode(",", $this->strip_comment($cc)));
             }


             if ($bcc != "") {
                 $TO = array_merge($TO, explode(",", $this->strip_comment($bcc)));
             }


             $sent = true;


             foreach ($TO as $rcpt_to) {
                 $rcpt_to = $this->get_address($rcpt_to);


                 if (!$this->smtp_sockopen($rcpt_to)) {
                     $this->log_write("Error: Cannot send email to " . $rcpt_to . "\n");


                     $sent = false;


                     continue;
                 }


                 if ($this->smtp_send($this->host_name, $mail_from, $rcpt_to, $header, $body)) {
                     $this->log_write("E-mail has been sent to <" . $rcpt_to . ">\n");
                 } else {
                     $this->log_write("Error: Cannot send email to <" . $rcpt_to . ">\n");


                     $sent = false;
                 }


                 fclose($this->sock);


                 $this->log_write("Disconnected from remote host\n");
             }


             return $sent;
     }


     /* Private Functions */


     function smtp_send($helo, $from, $to, $header, $body = "")
     {
             if (!$this->smtp_putcmd("HELO", $helo)) {
                 return $this->smtp_error("sending HELO command");
             }
             // auth
             if ($this->auth) {
                 if (!$this->smtp_putcmd("AUTH LOGIN", base64_encode($this->user))) {
                     return $this->smtp_error("sending HELO command");
                 }


                 if (!$this->smtp_putcmd("", base64_encode($this->pass))) {
                     return $this->smtp_error("sending HELO command");
                 }
             }


             if (!$this->smtp_putcmd("MAIL", "FROM:<" . $from . ">")) {
                 return $this->smtp_error("sending MAIL FROM command");
             }


             if (!$this->smtp_putcmd("RCPT", "TO:<" . $to . ">")) {
                 return $this->smtp_error("sending RCPT TO command");
             }


             if (!$this->smtp_putcmd("DATA")) {
                 return $this->smtp_error("sending DATA command");
             }


             if (!$this->smtp_message($header, $body)) {
                 return $this->smtp_error("sending message");
             }


             if (!$this->smtp_eom()) {
                 return $this->smtp_error("sending <CR><LF>.<CR><LF> [EOM]");
             }


             if (!$this->smtp_putcmd("QUIT")) {
                 return $this->smtp_error("sending QUIT command");
             }


             return true;
     }


     function smtp_sockopen($address)
     {
             if ($this->relay_host == "") {
                 return $this->smtp_sockopen_mx($address);
             } else {
                 return $this->smtp_sockopen_relay();
             }
     }


     function smtp_sockopen_relay()
     {
             $this->log_write("Trying to " . $this->relay_host . ":" . $this->smtp_port . "\n");


             $this->sock = @fsockopen($this->relay_host, $this->smtp_port, $errno, $errstr, $this->time_out);


             if (!($this->sock && $this->smtp_ok())) {
                 $this->log_write("Error: Cannot connenct to relay host " . $this->relay_host . "\n");


                 $this->log_write("Error: " . $errstr . " (" . $errno . ")\n");


                 return false;
             }


             $this->log_write("Connected to relay host " . $this->relay_host . "\n");


             return true;;
     }


     function smtp_sockopen_mx($address)
     {
             $domain = ereg_replace("^.+@([^@]+)$", "\1", $address);


             if (!@getmxrr($domain, $MXHOSTS)) {
                 $this->log_write("Error: Cannot resolve MX \"" . $domain . "\"\n");


                 return false;
             }


             foreach ($MXHOSTS as $host) {
                 $this->log_write("Trying to " . $host . ":" . $this->smtp_port . "\n");


                 $this->sock = @fsockopen($host, $this->smtp_port, $errno, $errstr, $this->time_out);


                 if (!($this->sock && $this->smtp_ok())) {
                     $this->log_write("Warning: Cannot connect to mx host " . $host . "\n");


                     $this->log_write("Error: " . $errstr . " (" . $errno . ")\n");


                     continue;
                 }


                 $this->log_write("Connected to mx host " . $host . "\n");


                 return true;
             }


             $this->log_write("Error: Cannot connect to any mx hosts (" . implode(", ", $MXHOSTS) . ")\n");


             return false;
     }


     function smtp_message($header, $body)
     {
             fputs($this->sock, $header . "\r\n" . $body);


             $this->smtp_debug("> " . str_replace("\r\n", "\n" . "> ", $header . "\n> " . $body . "\n> "));


             return true;
     }


     function smtp_eom()
     {
             fputs($this->sock, "\r\n.\r\n");


             $this->smtp_debug(". [EOM]\n");


             return $this->smtp_ok();
     }


     function smtp_ok()
     {
             $response = str_replace("\r\n", "", fgets($this->sock, 512));


             $this->smtp_debug($response . "\n");


             if (!ereg("^[23]", $response)) {
                 fputs($this->sock, "QUIT\r\n");


                 fgets($this->sock, 512);


                 $this->log_write("Error: Remote host returned \"" . $response . "\"\n");


                 return false;
             }


             return true;
     }


     function smtp_putcmd($cmd, $arg = "")
     {
             if ($arg != "") {
                 if ($cmd == "") $cmd = $arg;


                 else $cmd = $cmd . " " . $arg;
             }


             fputs($this->sock, $cmd . "\r\n");


             $this->smtp_debug("> " . $cmd . "\n");


             return $this->smtp_ok();
     }


     function smtp_error($string)
     {
             $this->log_write("Error: Error occurred while " . $string . ".\n");


             return false;
     }


     function log_write($message)
     {
             $this->smtp_debug($message);


             if ($this->log_file == "") {
                 return true;
             }


             $message = date("M d H:i:s ") . get_current_user() . "[" . getmypid() . "]: " . $message;


             if (!@file_exists($this->log_file) || !($fp = @fopen($this->log_file, "a"))) {
                 $this->smtp_debug("Warning: Cannot open log file \"" . $this->log_file . "\"\n");


                 return false;;
             }


             flock($fp, LOCK_EX);


             fputs($fp, $message);


             fclose($fp);


             return true;
     }


     function strip_comment($address)
     {
             $comment = "\([^()]*\)";


             while (ereg($comment, $address)) {
                 $address = ereg_replace($comment, "", $address);
             }


             return $address;
     }


     function get_address($address)
     {
             $address = ereg_replace("([ \t\r\n])+", "", $address);


             $address = ereg_replace("^.*<(.+)>.*$", "\1", $address);


             return $address;
     }


     function smtp_debug($message)
     {
             if ($this->debug) {
                 echo $message . "
;";
             }
     }
}